A variety of brakes have been proposed for bicycles. These brakes include chain brakes, hub-mounted disc brakes, and the rim brake, among others. In general, rim brakes utilize one or more pads to press against the outer surface of the wheel rim adjacent the tire in order to generate a braking force.
Prior rim brakes suffer from a number of drawbacks. First, it is desirable for the brake to be lightweight. Some brakes are very effective, but extremely heavy. Second, the brake must be reliable and effective in operation. For example, some brakes are relatively lightweight but suffer from one or more disadvantages, such as requiring a high user application force or having an uneven braking action or poor braking force.
For example, U.S. Pat. No. 3,628,635 discloses a side-pull lever rim-type brake. As disclosed, the brake is constructed so that “a small tensile force can achieve a big brake effect.” On the other hand, this brake design suffers from several drawbacks. First, the configuration of the brake makes the brake large in dimension. When the brake is activated, the lever arm (16) thereof rotates upwardly and outwardly. In this position, the arm (16) protrudes outwardly from the brake and may pose a hazard, such as to the body of a rider. In addition, while a large lever action is created, braking effect can not be well controlled or adjusted, as the braking force is applied to the far side of one of the arch members.
U.S. Pat. No. 7,000,739 discloses a later attempt to create a compact and efficient brake. This brake uses a cam-type lever (52). The lever (52) is mounted to one arm (14) for pivoting, and engages a second arm (12). Movement of the lever presses the two arms (and brae shoes thereon) towards one another. This design is an improvement over the above-described brake in that this brake is more compact. Yet, the design still requires a long lever arm in order to effect sufficient braking (which adds weight to the brake and limits the compactness of the brake).